It is easy for a journalist in a rush to describe a Nazi death camp with the country of its location. "The Polish concentration camp Auschwitz," one often reads. This is understandably infuriating to some of those with roots in those countries, who watch closely for the practice, demanding that, for example, Treblinka is referenced as "built by Nazi Germany in occupied Poland during World War II," which is exactly how it reads on Wikipedia. Anything but "the Polish camp Treblinka," with its connotations of blame, echoing down through the decades.

So when Jan Tomasz Gross, a Polish-born American historian, published "Neighbors: The Destruction of the Jewish Community in Jedwabne, Poland" in 2001, there was a storm of protest in Poland. In essence, Gross argued that the almost all of the Jews of Jedwabne were massacred — knifed, bludgeoned and burned en masse — not by German soldiers, as previously thought, but by their fellow Poles, their classmates, those who had once joined them in schoolyard games. This was not a handful of people; Gross wrote of 1,600 bodies, about half of the small town in northeast Poland. A review of that book referred to the town's people as "Hitler's willing executioners."

That word, "classmate," rings throughout "Our Class," the harrowing piece of theater on offer from the Remy Bumppo Theatre Company — the biggest risk this company has taken in staging the first Chicago production of this theater piece, penned by the Polish playwright Tadeusz Slobodzianek. It is based on Gross' book and tells his story of what happened in Jedwabne.

Actually, the piece tells a greater story in formidable detail, beginning with when the victims and murderers were all friends together in grade school — charting the events (such as the arrival of the Soviet army) that led up to the slaughter itself and its messy aftermath, as the truth began to filter out and those who were there, and who survived, tried to make some sense of the rest of their lives.

Slobodzianek's play, which was hailed by many in Poland, winning a prestigious prize, was adapted into English by Ryan Craig. It uses a cast of 10 actors, who play their characters from youth to old age. It has been seen at London's National Theatre, in Toronto and in Wilmington, Del., which staged the U.S. premiere in 2011. It has not, until now, been seen in Chicago.

And it is not to be missed.

To some extent, Slobodzianek's play explores this unconscionable event not dissimilarly from the way "The Laramie Project" looks at the murder in Wyoming of young gay man Matthew Shepard, or how Anna Deavere Smith approached her "Fires in the Mirror." There are echoes of "The Lottery" in its study of mob brutality. It is a fusion of the narrative and the dramatic, probing multiple points of view. But in Chicago, director Nick Sandys' formidable ensemble production (the best work I've seen to date from this actor-director) will put longtime fans of off-Loop theater in mind of "Ghetto," the memorable production with similarly heart-wrenching themes, created by the defunct Famous Door Theater Company.

The actors in Sandys' cast go to some dark places in service of their storytelling. Among very many fine performances, it's hard to quickly forget David Darlow's guilt-ridden character Abram, who escaped to America before so many of his classmates perished. Nor does one's head quickly erase Matthew Holzfeind, who portrays the most terrifying of the thugs, nor Rebecca Sohn, who plays another survivor, if that is the word, a young Jewish woman who converted to Christianity to save her life. Sohn's Rachelka, renamed Marianna, married a Catholic man, played with formidable and loathsome complexity by Matthew Fahey, whose rebellion was as pathetic as it was essential.

The event at the center of the play is, of course, a horror of singular brutality. But the piece understands that complicity is complicated, charting how people got to this point — not that it even remotely excused their actions — and then focusing, in the quieter but equally intense Act 2, on a truth that somehow hit me uncommonly hard on Sunday afternoon. So many years went by before the events came to light that, for those still alive, it was just too late to mean anything. There are many plays about the murder of Jewish people in the 1930s and 1940s; few are the pieces that carry the weight of these acts so far or analyze them in such depth. There are no innocents here: Americans, the play argues, chose to find out little and did less.

This is a Chicago-style show in the best aspects of the term: furious energy, small theater, unstinting pain, sublimation of the individual into ensemble. You will also see Linda Gillum, Dennis Williams Grimes, Aram Mosinoff, Brian Plocharczyk, Rachel Shapiro and Stephen Spencer. Remy Bumppo has often made safe theatrical choices in the past. Not here. The visual environment, with projections created by John Boesche, is arrestingly beautiful, which might not be an adjective you expect.

There are those who have argued that this piece is less than accurate or fair. As a work of theater, it is long and hard to watch; there is the odd sag, the odd moment that doesn't ring true. But this strikes me as one of those essential shows this town's theaters unleash on us from time to time. It makes you wonder how those who lived through this, or one of the other versions of it, ever found the strength to draw another breath. Had they not, of course, we would not have their story.

A 19-year-old Portsmouth woman is facing multiple charges following a police pursuit that ended in Newport News over the weekend and involved two children reported missing in Chesapeake, an official said.